| We may never truly know when writing was invented. There's a stele that was discovered in 1986 [1] in Veracruz. You could be forgiven if you think that writing is Maya. But it is not. It some other language. A couple other small fragments like it have been found, but the stele is basically an hapax. It is the only example. And from the one example, we can see that it a system overflowingly glorious in its maturity and complexity. The scribes belonged to a culture that had been writing for a very long time. That is the refinement of millennia. There are dates carved on La Mojorra 1; if they are in the same Long Count calendar the Maya used, then the stele appears to be talking about something that happened in the 140s and 150s AD. The obvious relationship between the Mesoamerican writing systems might be somewhat analogous to the Cyrillic and Latin alphabets, or Chinese and Japanese writing. One was adapted to write the other. Or they both evolved out of a common ancestral system. How far back might that have been? [1] https://commons.wikimedia.org/wiki/File:La_Mojarra_Stela_1_S... |
But... IDK if this (or other clearly advanced writing systems) demonstrate "refinement of millennia."
I think we have a "history is accelerating" bias. Changes in the deep past happened slowly, and the pace of change increases over time. That may be true from a very broad POV... but I don't think it's true on shorter timescales.
There are no hard limitations on going from a newly invented writing system to a professional scribal culture in a single generation. I don't think watershed "revolutions" are something new. Egyptian writing, and Early bronze age egyptian culture more broadly gets very advanced, very quickly. We don't really know what elements have deep histories... but it's hard to explain ancient egypt without allowing for some impressive leaps. Hence aliens.
Also... "common ancestor" can be a lot of things. It could be like the gradual species-like philogenetics of cyrillic, latin, hebrew, arabic and all other alphabets' development from proto-sinaitic and canaanite/punic. The same script gradually evolving in different scriptural islands.
Otoh... "ancestry" can be pure inspiration. The idea of writing, its uses and the certainty that widespread literacy is possible can be the "dna."
The confusing part is that culture does, often, evolve very gradually like species and clades over time. These sometimes leave evidence of the whole process. Sudden explosions can't be deduced from the absence of evidence.